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Brains in Bahrain
In October 2002, Vladimir Kramnik and Deep Fritz competed in the eight-game Brains in Bahrain computer chess match, which ended in a draw.
Kramnik won games 2 and 3 by "conventional" anti-computer tactics - play conservatively for a long-term advantage the computer is not able to see in its game tree search. Fritz, however, won game 5 after a severe blunder by Kramnik. Game 6 was described by the tournament commentators as "spectacular". Kramnik, in a better position in the early midgame, tried a spectacular piece sacrifice to achieve a strong tactical attack, a strategy known to be highly risky against computers who are at their strongest defending such attacks. True to form, Fritz found a watertight defence and Kramnik's attack petered out leaving him in a bad position. Kramnik resigned the game, believing the position lost. However, post-game human and computer analysis has shown that the Fritz program was unlikely to have been able to force a win and Kramnik effectively sacrificed a drawn position. The final two games were draws. Given the circumstances, most commentators still rate Kramnik the stronger player in the match.
Fritz had been chosen to play Kramnik by winning a qualifying event in Cadaques, Spain. The other competing program was Junior, the then World computer chess champion Shredder was not invited to compete. The 24 game match started very poorly for Fritz losing five games in a row before the program came back strongly in the last ten games to tie the series and then go on to win the play-off. Fritz became Deep Fritz when the hardware was extended to an eight-processor machine for the competition.
Kramnik was given several advantages in his match against Fritz when compared to most other Man vs Machine matches, such as the one Garry Kasparov lost against Deep Blue. The code of Fritz was frozen some time before the first match and Kramnik was given a copy of Fritz to practice against for several months. Another difference was that in matches lasting more than 56 moves Kramnik was allowed to adjourn until the following day and use Fritz to aid him in his overnight analysis of the position.